COL4A3 and lung cancer: Li et al. (2020) claimed that COL7A1 may act as a crucial gene affecting the progression of hypoxia-related LUAD via DNA methylation. Unlike COL7A1, COL4A3 is expressed at low levels in lung cancer tissue. Metodieva et al. (2011) found that the expression of COL4A3 genes was upregulated in early NSCLC, while in another study, patients with lower COL4A3 expression shared a longer median OS (Jiang et al., 2013), confirming that it may act as a biomarker of LC. It has been reported that DNA repair can be weakened by blocking the interaction between COL4A3 proteins (Stabuc-Silih et al., 2009).